<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>进度条动画</title>
</head>
<style>
  div {
    display: inline-block;
  }
  .con>div {
    width: 20px;
    height: 100px;
    background-color: #ddf;
    border-radius: 1rem;

    -webkit-animation-name: my;
    -webkit-animation-duration: 1.2s;
    -webkit-animation-iteration-count: infinite;
    -webkit-animation-timing-function: ease-in-out;
  }

  @-webkit-keyframes my {
    0% {
      -webkit-transform: scaleY(0.4);
    }
    20% {
      -webkit-transform: scaleY(1);
    }
    50% {
      -webkit-transform: scaleY(0.4);
    }
    100% {
      -webkit-transform: scaleY(0.4);
    }
  }

  .con>div:nth-child(2){
    -webkit-animation-delay: 0.1s;
  }
  .con>div:nth-child(3){
    -webkit-animation-delay: 0.2s;
  }
  .con>div:nth-child(4){
    -webkit-animation-delay: 0.3s;
  }
  .con>div:nth-child(5){
    -webkit-animation-delay: 0.4s;
  }
  .con>div:nth-child(6){
    -webkit-animation-delay: 0.5s;
  }

</style>
<body>
<div class="con">
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
</div>
</body>
</html>